Cargo ships sail through the Suez Canal near Ismailia, Egypt. Terroriststried to disrupt navigation in the waterway by targeting a Panama-flagged ship. / AP AP

by Stephen Starr, Special for USA TODAY

by Stephen Starr, Special for USA TODAY

ISTANBUL - Attacks on vessels using Egypt's Suez Canal and increased terrorist activity in the Sinai Peninsula are opening up a new front in the war on terror, posing a serious threat to a crucial international trade route and with it global shipping, warn analysts.

Egyptian authorities have tightened security measures around the Suez Canal following intelligence suggesting Muslim Brotherhood supporters intend to target the key waterway today to coincide with the first day of trial for former president Mohamed Morsi.

Already terrorists have been probing the canal for weaknesses, say authorities.

On Aug. 31, an rocker-propelled grenade attack targeted the COSCO Asia container ship as it passed through the Suez Canal, while a separate attack on another vessel occurred July 29. Both attacks have been claimed by the Furkan Brigades, a new militant jihadist group operating in Egypt's Sinai Peninsula, though no significant damage was recorded in either incident.

"We can target the international water passage morning and night, along the entire length of the waterway," the group said in a video statement uploaded to YouTube shortly after the Aug. 31 attack. The Furqan Brigades has vowed more attacks.

The Egyptian military in early September launched one of the largest military operations in decades against militants to combat growing lawlessness and militant activity in the Sinai. Security forces found mortars and defused explosives in areas around the Suez Canal, and have been locked in fighting with Islamist militants in Sinai for almost two months.

The New York-based Soufan Group, a security consultancy warns that attacks by al-Qaeda-linked groups are likely to continue to target ships along the Suez Canal.

"The disruption and chaos that would result from disabling a large commercial vessel crossing the canal would be a significant propaganda victory for the perpetrators," a report by the group this month said.

The Suez Canal is a key shipping route for global trade with about seven percent of the world's oil and 13% of the international gas supply passing through the Suez Canal last year, according to the U.S. Energy Information Administration.

Nationalized in 1956, dozens of ships use the 120-mile canal every day, including the Maersk Mc-Kinney Moller, a massive new vessel launched by Maersk from South Korea in July that can transport the exceptionally large 18,000 20-foot (TEU) containers at a time. Maersk has 19 more 18,000 TEU ships on order and are expected to be sailing by 2015.

Other major shipping companies including China Shipping and United Arab Shipping Co. have also ordered the 18,000 TEU vessels built by South Korea's Daewoo shipbuilding company, according to Lloyds List Intelligence.

The emergence of a new generation of giant container ships, too big to pass through the world's other vital waterway â?? the Panama Canal â?? means that for the Asia-Europe and the Asia-eastern Americas shipping routes, the Suez Canal is poised to grow in importance in the coming years.

Such massive, slow-moving leviathans are easy targets for the Islamic militants that have been operating with general impunity in the Sinai Peninsula in recent years, say analysts.

"The sinking of a vessel in the Suez Canal would effectively shut the entire canal for several days, if not weeks, while the wreckage was broken up and removed," said a report published by the International Institute for Strategic Studies last month.

"(But) more likely is a spill â?¦ which may shut down the canal depending on the Suez Canal Authority's response and policy toward it," Christian Le Miere, the author of the IISS report, told USA Today, adding that it is still difficult to actually sink a ship. "Alternative routes do not exist other than round the southern Cape (of Africa), a much longer journey."

However, shipping giants Maersk are playing down the threat.

"We monitor the situation according to normal procedures and see a stable, unchanged situation in the Suez â?? therefore we have no special plans drawn up," said Mikkel Elbek Linnet, spokesperson for Danish shipping giant, Maersk.

The Suez Canal sees 800,000 barrels of oil and 1.4 million barrels of other petrochemicals pass through it every day. Containerized cargo made up over 70% of all non-energy cargo traffic during the first six months of this year, while over 13,000 vessels have passed through in 2013, according to the Suez Canal Authority. Analysts believe about 80% of container ships in operation today have armed security on board, highlighting the increasing threat to vessels.

"It would only take one successful attack on a large vessel traveling along the Suez to have the desired financial effect on both Egypt and the wider spheres of shipping and trade," said Charles Lister of IHS Jane's, an international security watchdog. "The August double RPG attack was carried out in broad daylight, which definitely demonstrates the ease with which potential militant threats could operate."